Changing practice of pelvic lymph node dissection in management of primary bladder cancer.

Background: Surgical management of bladder cancer has seen a significant period of change over the last decade. This has largely been driven by recognition of the importance of pelvic lymph node dissection (PLND) - yet debate still continues regarding the extent of dissection required. Our aim was to ascertain how the practice of PLND has evolved over the last decade in the setting of bladder cancer and cystectomy at a tertiary referral centre.

Methods: Analysis of a retrospectively collected database including all cystectomies conducted at a tertiary centre in the last 10 years. Cases of non-primary bladder cancer were excluded. Histopathology records were scanned for data regarding PLND. Extent of PLND was defined according to levels. These were numbered level 1 (perivesical, pelvic and obturator), level 2 (internal and external iliac) and level 3 (common iliac). Trends in extent of dissection and number of nodes harvested were assessed.

Results: One hundred and thirty cases of primary bladder cancer undergoing cystectomy were identified. Dissection to level 3 has increased from zero cases in 2005-2008 to 40% of cases in 2013-2015. We have seen a corresponding rise in number of lymph nodes collected. Increasing extent of dissection has improved staging by identifying positive nodes that would otherwise be missed.

Conclusions: The extent of PLND has increased over time. The current standard template at our institution includes a bilateral dissection of perivesical, obturator, internal iliac, external iliac and common iliac LN. This change has resulted in more accurate staging and increased total lymph node yield.